Anatomy: The Back

Question 1

What are the functions of the vertebral column?

Answer 1

PROTECTION - of spinal cord
SUPPORT - carries weight fo the body
AXIS - central axis of the body
MOVEMENT - posture and movement

Question 2

What is the vertebral body?

Answer 2

transfers the weight of the body - interconnected by ligaments and separated by intervertebral discs

Question 3

What is the vertebral arch?

Answer 3

Refers to the lateral and posterior parts of the vertebrae

Question 4

What is the vertebral foramina?

Answer 4

Foramina of each vertebrae form the vertebral canal which houses the spinal cord

Question 5

Where are the articular processes?

Answer 5

arise between the pedicles and the laminae with a superior and inferior process on each side - each has articular facet (superior has it on their dorsal surface and inferior has it on their ventral surface)

Question 6

What are the spinous processes?

Answer 6

processes that project posteriorly and can be palpated

Question 7

What are the transverse processes?

Answer 7

These processes project laterally or torso-laterally on both sides and are important for muscle attachment

Question 8

What are the laminae?

Answer 8

the bone between the spinous and transverse processes

Question 9

What are the pedicles?

Answer 9

There are 2, one on either side and they point posteriorly to meet the flatter laminae

Question 10

What are the key features of cervical vertebrae?

Answer 10

Smallest vertebral body as it only has to support the weight of the head
Largest vertebral foramina
C1: no spinous process
C2-C6: spinous process has a prominent notch
C7: spinous process is similar to T1 - thick and projects dorsally and attaches inferior end of nuchal ligament

Question 11

What are the interesting features of atlas?

Answer 11

C1 articulates with the occipital condyles to enable nodding
- lacks a vertebral body and spinous process
Articulates with axis to permit rotation

Question 12

What are the interesting features of axis?

Answer 12

During development the body of the atlas fuses with the axis to create the DENS (odontoid process) - muscles attach to the prominent spinous process to control positioning of the head and neck

Question 13

What is important about the dens in children?

Answer 13

Fusion of the dens and axis is incomplete in children, therefore accidents or severe shaking can lead to dislocation

Question 14

What are the key features of thoracic vertebrae?

Answer 14

Distinctive heart shaped vertebral body (larger than cervical because it has to withstand more weight)
Smaller vertebral foramen
Long slender spinous process that projects posteriorly
Costal facets of vertebral bodies are for the ribs to articulate

Question 15

What are the key features of the lumbar vertebrae?

Answer 15

Largest Vertebrae - withstands the most weight
No costal facets
Transverse processes project torso-laterally
Vertebral foramen is triangular shaped
Spinous process projects dorsally

Question 16

How is the sacrum formed?

Answer 16

Five components of the sacrum fuse together and this is usually complete by 25-30 years of age

Question 17

What is the key function of the sacrum?

Answer 17

Protects the reproductive, digestive and urinary organs

Question 18

What is the sacral promontory?

Answer 18

Bulge at the anterior tip of the base which is a key landmark in labour and pelvic examinations

Question 19

What are the coccyx?

Answer 19

They are formed of 3-5 vertebrae which begin fusing at about 26

Question 20

What are the primary curves of the vertebra?

Answer 20

Develop before birth

• Thoracic curve - to accommodate thoracic organs
• Sacral curve - to accommodate abdominopelvic organs

Question 21

What are the secondary curves of the vertebra?

Answer 21

Develop after birth
Cervical curve - develops as infant begins balancing weight of head on the neck of the vertebra
Lumbar curve - develops as infant starts learning to stand and balances weight of the trunk on the lower limbs

Question 22

What are the deep back muscles and what is their main function?

Answer 22

Superficial: Splenius capititis, Splenius Cervicis
Intermediate: Illiocostalis, Longissimus, Spinalis
Deep: Semispinalis, Multifidus, Rotatores, Minor deep intrinsic muscles

Movement of the vertebral column

Question 23

What nerve innervates all of the deep back muscles?

Answer 23

Posterior rami of spinal nerves

Question 24

What is the main role of the superficial deep back muscles?

Answer 24

Rotate head to same side

Question 25

What is the main role of the intermediate deep back muscles?

Answer 25

laterally flex vertebral column (unilaterally) and extend vertebral column and head (bilaterally)

Question 26

What are the main roles of the deep deep back muscles?

Answer 26

Extends and contralaterally rotates head and vertebral column
Stabilises vertebral column

Question 27

What is the key role of the intermediate back muscles and what are they?

Answer 27

Movement of thoracic cage
Serratus posterior superior
Serratus posterior inferior

Question 28

What nerve innervates the intermediate back muscles?

Answer 28

Intercostal nerves

Question 29

What are the individual functions of the two intermediate back muscles?

Answer 29

Serratus posterior superior- raises ribs 2-5

Serratus posterior inferior - depresses ribs 9-12

Question 30

What is the key role of the superficial back muscles and what are they?

Answer 30

Movement of shoulders 
Trapezius 
Lattisimus dorsi 
Levator scapulae
Rhomboids (major and minor)

Question 31

What nerves innervates the superficial back muscles?

Answer 31

Trapezius - motor innervation is the accessory nerve and receives proprioceptor fibres from C3 and C4 nerves

Lattisimus dorsi- thoracodorsal nerve

Levator scapulae and Rhomboids- dorsal scapular nerve

Question 32

What are the main functions of the trapezius muscle?

Answer 32

Upper fibres= elevate scapula and rotate arm during abduction
Middle fibres = retrace scapula
Lower fibres = pull scapular inferiorly

Question 33

What are the main functions of the Latissimus dorsi muscle?

Answer 33

extends, adducts and medially rotates upper limbs

Question 34

What are the main functions of the Levator scapulae muscle?

Answer 34

elevates scapula

Question 35

What are the main functions of the rhomboids muscle?

Answer 35

retracts and rotates scapula

Question 36

What covers the vertebral body surfaces and what are they attached to?

Answer 36

Covered by hyaline cartilage and are attached to intervertebral discs by fibrocartilage

Question 37

What is the importance of anterior and posterior longitudinal ligaments attaching to the vertebral body joints?

Answer 37

They strengthen these joints and prevent hyperextension (Mainly the anterior one, as it is thicker)

Question 38

What is the importance of facet joints?

Answer 38

Between the articular facets- enable gliding motion between the vertebrae

Question 39

What are the ligaments involved in strengthening the facet joints and where are they positioned?

Answer 39

Ligamentum flavus - from lamina to lamina

Interspinous and supraspinous ligaments - join spinous processes
(inter = attache between processes and supra = attach to the tips)

Intertransverse ligaments = between transverse ligaments

Question 40

What is scoliosis?

Answer 40

Abnormal lateral curvature of the spine in one or more of the moveable vertebrae

Symptoms: shoulders aren’t level, uneven waist, one shoulder blade can appear more prominent than the other and one hip can be higher than the other

Girls are at greater risk of condition worsening - tends to occur before puberty during a growth spurt

Question 41

What are the causes of scoliosis?

Answer 41

Developmental problems - birth defect

Neuromuscular problems - cerebral palsy or muscular dystrophy

Injuries to the spine

Infection of the spine

Question 42

What is kyphosis ?

Answer 42

the normal thoracic curvature becomes exaggerated posteriorly creating a “round back” - curvature greater than 45 degrees = exaggerated

Causes pain, tenderness of spine and fatigue- tend to get worse over time and can cause difficulty with breathing and eating

Question 43

What are the causes of kyphosis?

Answer 43

Poor posture
Scheuermann’s kyphosis - abnormally shaped vertebrae due to development problem
Congenital kyphosis - sometimes 2 or more vertebrae fuse together
Age - as we age our spinal curvature increases

Question 44

What is lordosis?

Answer 44

“swayback”- both abdomen and buttocks protrude abnormally = anterior exaggeration of the lumbar curvature - it can be seen in pregnant women

Question 45

What are the causes of lordosis?

Answer 45

Spondylothesis - lower vertebra slips anteriorly onto the bone below
Osteoporosis - loss of bone density
Obesity - increased pressure
Osteosarcoma

Question 46

What does the lumbar puncture needle have to pass through?

Answer 46

Skin 
Subcutaneous layer 
Back muscles
Supraspinous ligament 
interspinous ligament 
ligamentum flavus 
epidural space
dura mater
arachnoid mater 
into the subarachnoid space